Honey has a density of about 1.36 kilograms per litre (36% denser than water).[43]Isotope ratio mass spectrometry can be used to detect addition of corn syrup or sugar cane sugars by the carbon isotopic signature. Addition of sugars originating from corn or sugar cane (C4 plants, unlike the plants used by bees, which are predominantly C3 plants) skews the isotopic ratio of sugars present in honey, but does not influence the isotopic ratio of proteins; in an unadulterated honey, the carbon isotopic ratios of sugars and proteins should match. As low as 7% level of addition can be detected.[44]